A total of 1,534 pregnant women in Japan took a new type of prenatal testing intended to detect possible chromosome abnormalities in their unborn babies in the three months after the method was launched in April, it was learned Wednesday.
The test, which involves simple maternal blood sampling and is thus safe, was conducted at 22 medical institutions nationwide.
The number of women who took the test in the three-month period far exceeded the roughly 1,000 a year estimated by a study group comprising hospitals and other medical institutions designated to carry out the new prenatal testing.
This reflects a growing interest in the prenatal diagnosis as late-in-life pregnancy is on the rise, the group said.
Of the 1,534 women who took the test, 29 people, or 1.9 percent, received test results that indicated possible chromosome abnormalities in the fetuses. Down syndrome was suspected for the fetuses of 16 women, trisomy 18 syndrome for nine and trisomy 13 syndrome for four.
Detailed conditions were known for 11 of the 29 women. Among them, fetal chromosome abnormalities were confirmed for at least six women through follow-up testing, including amniotic fluid sampling, and at least two of them opted to terminate their pregnancies.
Additional tests found no abnormalities for two of the five others, while one woman had a spontaneous abortion. The remaining two are still waiting for final test results.
The 1,534 women who took the new prenatal testing were aged between 27 and 47, with their average age standing at 38.3. Asked about the reasons for taking the new prenatal testing, 94.1 percent referred to their age.
At least 12 people decided not to take the test after receiving counseling.